Excavating machine



March 3, 1936. R, L. BROWN EXCAVATING MACHINE Filed Oct. 26, 1933 5 Sheets-Sheet 1 I INVENTOR. 62M X 1,01 31 BY 5, w gzoQ h/gfim v 77 ATTORNEYS.

March 3, 1936. R. L. BROWN EXCAVATING MACHINE Filed Oct. 26, 1933 5 Sheets-Sheet 2 II HK \ulll IlIll I INVENTOR.

M, We

I WSWWYM A TTORNEYS.

March 3', 1936. R. BROWN EXCAVATING" MACHINE Filed Oct. 26, 1933 5 Sheets-Sheet 3 v A TTORNEYS.

INVENTOR.

March 3, 1936. R, I Q N I 2,032,911

EXCAVATING MACHINE Filed Oct. '26, 1933 5 Sheets-Shet 4 INVENTOR. I WLAKX. M

March 3, 1936.

R. 1.. BROWN 2,032,911

EXGAVATING MACHINE Filed 09's. 26, 1933 5 Sheets-Sheet 5 lI/II/l/II/I/IIIIII;

III/

I N VEN TOR.

1 ATTORNEYS.

Patented Mar. 3, 1936 UNITED STATES PATENT OFFICE 17 Claims.

This invention relates in general to excavators and more especially to earth and material handling machines for such purposes as cutting grades, digging in borrow pits, digging base- 5 ments, drainage and irrigation ditches, mine stripping, digging through heavy snow drifts not movable by plow, backfilling ditches, loading sand, gravel and crushed stone as well as for other various uses and applications.

One of the novel characteristics of the machine is that its digging action is a continuous motion of excavation, lost motion due to placing excavated material at a desired point and coin sequently detracting from the productive capacity 3:, of the machine being eliminated. Because of this fact, it is estimated that an excavating machine embodying the present invention will excavate at least twice as much material as other types of machines with corresponding powerv Also the machine will weigh not more than one-third. as much as present machines of corresponding power and consequently will cost less initially and cost less to operate.

. In the construction of a machine embodying the present invention a further economy is realized in its fabrication by virtue of the use of a stand ard track type tractor of suitable construction to provide power for the digging member and discharge conveyor and also power for traction so when the machine is being moved from job to job as well as the slower feed traction speed for forcing the machine into the material to be excavated. Moreover, provision is made for imparting a very slow motion to the digging mem- 11; her to force it into the material in a controlled arcuate movement which will not exceed but will be almost a 180 maximum.

It is to be understood, of course, that while a tractor unit is used for power it is possible to in use any suitable power plant and transmission unit for the purposes which the tractor serves. A tractor is, however, desirable because of its economical cost, its high quality construction and its adaptability to the purpose. Another advantage which flows from the use of a tractor resides in the fact that it is entirely practical to reclaim the tractor for other purposes when the excavator is not at work and it is desirable m to do so.

Another object of the invention resides in the provision of an excavating machine of this character which is simple and durable in its construction, reliable and efficient in its operation, sus- 5 cepti-ble of convenient control and easy andcom paratively inexpensive to manufacture, operate and maintain.

Other objects and advantages reside in certain novel features of the construction, arrangement and combination of parts which will be hereinafter more fully described and particularly point- M ed out in the appended claims, reference being had to the accompanying drawings, forming a part of this specification, and in which:

Figure 1 is a perspective view showing one em- 10 bodiment of the invention;

Figure 2 is a diagrammatic view in plan further illustrating the embodiment of the invention shown in Figure 1; I

Figure 3 is a view similar to Figure 2 but showing a machine in side elevation;

Figure 3a is a diagrammatic view in end elevation to illustrate certain of the chain and sprocket gearing employed;

Figure 4 is a fragmentary sectional view taken on line 4- of- Figure 5 and showing the turntable, digging wheel and associated parts employed at the forward end of the machine, parts being omitted and parts being shown in section for the sake of illustration;

Figure 5 is a view in sect-ion taken on line 5-5 of Figure 4 and with parts shown in elevation for the sake of simplicity in illustration;

Figure 6 is a fragmentary view taken on line 6-5 of Figure '7 and with parts shown in elevation for the sake of illustration;

Figure 6a is a detail view showing the beveled structure of the cutting blades;

Figure '7 is a view in elevation looking toward the rear of the digging wheel, the parts connected therewith being omitted for the sake of illustration Figure 8 is a view in vertical section taken on line 88 of Figure '7, parts being shown in elevation-for the sake of illustration;

Figure 9 is a diagrammatic view in side elevation illustrating generally how the motor and transmission is connected up to the slow speed drive for the swing gear;

Figure 10 is a View partly in side elevation and partly in longitudinal vertical section illustrating the features of the construction of the slow speed drive for the swing gear and associated parts;

Figure 11 is a view in horizontal section taken on line lll l of Figure 10 and with parts shown in elevation for the sake of simplicity in illustration;

Figures 12 and 13 are views taken on lines |2-l-2 and Iii-l3, respectively,v of Figure 1 1 Figure 14 is a fragmentary view similar to Fig- 16 a a turntable 2.

ure 11 but showing a slight modification of the structure; and

Figure is a View in transverse section taken on line Iii-I5 of Figure 14.

Referring to the drawings, and more especially to Figures 1 to 3, inclusive, it will be seen that the present embodiment of the invention proposes the use of a tractor designated generally at T which may be of any standard type and construction appropriate to the present use. The tractor has, as usual, a power plant P, frame members F, self-laying tracks Sand various other conventional features.

Rollers I which are mounted for rotation on the forward end of the tractor serve to support The turntable 2 is constrained to rotate about a; fixed axis by means of a hollow center pin or gudgeon 3 suitably secured to the frame of the tractor and fitted in a vertical hearing sleeve =i integral with or fixed to the turntable 2. A pair of transversely spaced and vertically extending standards or frame members 5 are securely fixed to the turntable so as to be constrained to move therewith.

Forwardly of the turntable 2 and its standards 5 a digging wheel designated generally at 6 is provided and is supported for rotation about a horizontally disposed axis extending generally fore and aft of the machine as will hereinafter more clearly appear.

As shown in Figures 1, 6, 7 and 8, the digging wheel 6 comprises a pair of spaced body plates I and 8 of annular form and securely bolted or otherwise fastened to ring gears 9 and I0. At angularly spaced intervals digging buckets II are provided between the plates I and 8 and have their side walls I2 securely bolted or otherwise fastened to these body plates. The body portions I3 of the buckets are provided with digging teeth I4. To support the digging wheel for rotation and to provide for the drive of the same a box-like support I5 is disposed within the wheel. This support I5 is fabricated of plates and angles or other suitable structural elements. Three bearing brackets it are provided at spaced points on the support I5 and receive the shaft H which support three pairs of flanged rollers I8, these flanges rollers engaging the body plates 1 and 8 and plain portions of the ring gears 9 and I0 to mount the digging wheel for rotation. The support of the ring gear is completed and its drive is provided for by virtue of the provision of pinions I9 and mounted on the opposite ends of a short shaft 2I supported for rotation in bearings provided therefor in a gear casing 22 secured to the support I5. The pinions I9 and if!) mesh with the teeth of the ring gears 9 and II), respectively.

Cast integral with the ring gear I I) or otherwise suitably connected with the digging wheel are lugs 23 which provide supports for the outer ends of cutting blades 24, the latter being provided if desired with cutting teeth 25. The inner ends of the blades or cutters 24 are securely fasconnected as at 33 to brackets 34 securely fastened to the box-like support l5. Similarly, the rearward ends of the upper links have a pivotal mounting designated at 35 on bearin sleeves 36 carried by the frame-members 5, while their forward ends are formed with bearings 31 through which a shaft 33 extends, the shaft 38 being supported by bearing brackets 39 secured to the support I5. These links 35 and 3| are constrained to move up and down vertically with respect to the turntable and its standards 5 by virtue of the provision of fixed vertical guides 40 in the form of channels which are securely interconnected with the turntable and its standards 5. The digging wheel, while thus adjustable vertically with respect to the turntable is positively constrained to swing therewith and receives a positive thrust therefrom.

Any suitable mechanism may be provided for raising and lowering the digging wheel. For the sake of illustration a hoisting mechanism is shown as being made up of hoist lines 4| and 42; each of which has one end dead-ended as at 43 on the standards 5, has its intermediate portion extending around a sheave M mounted on the ends of the shaft 38 and has its other end secured to and wound about hoist drums i5 fixed on a shaft 46. The shaft 46 is mounted for rotation in bearing brackets 48 and is actuated from a suitable power source or through a worm and worm wheel 49 from a hand crank 50. The material excavated by the wheel 6 is deposited on a conveyor 55, one end of which projects into the digging wheel and the other end of which extends back between the standardsS of the turntable. Delivery of the excavated material from the digging buckets onto the conveyor 55 is insured by the provision of a shield or track 56 (see Figure 7 over which the buckets travel as they move upwardly after exerting their excavating action and by the provision of a-trough 5! provided at the upper end of the shield and insuring discharge onto the conveyor. It will be understood that the shield 55 together with the trough 51 are mounted on the support I5.

The conveyor 55 comprises an endless belt 58 trained about supporting and driving rollers 59 and 50. The roller 5!! is fixed to a shaft 5| (see Figure 6) journaled for rotation in a bearing 62 provided on the supporting box i5 and also in a bearing 63 provided in the gear casing 22. The roller 59 is similarly fixed to a shaft 64, one end of which is mounted for rotation in the sleeve bearing 36 (see Figure 4) and the other end of which is mounted in a similar sleeve bearing '65 carried by the opposite standard 5 of the turn: table.

The conveyor 55 discharges onto a second or spoil conveyor designated generally at 10 and which has one end underlying the conveyor 55 in all of its positions and has its opposite end positionable to discharge clear of the machine and either onto a spoil bank or into a truck or otherwise as may be desired. The conveyor 10 comprises an endless belt II trained about a lower driving roller 12 and an upper idler roller T3. The roller 72 (see Figure 5) is fixed to a shaft 14 journaled. in bearings provided in the upright arm E5 of a yoke-like swivel frame 15.

The frame 76 has a sleeve-like bearing 11 which like frame I9 has its arms provided with extensions 89 (see Figure 3) to which the lower end of conveyor frame members 8| are pivotally connected as at 82. The opposite ends of these frame members BI are equipped with bearing members 83 for the shaft of the idler roller 13. With this construction the conveyor 19 may be raised and lowered vertically under the influence of a hoisting mechanism designated generally at and which may be of any suitable construction. It may be power driven or may have its hoist lines controlled by one or more winding drums 88 actuated by worm gearing 8'! from a hand crank 88.

A common drive is provided for the digging wheel 6 and the conveyors 55 and 19.

Referring now to Figures 2, 3, 3a, 4, and 5, it will be seen that this common drive is taken from a sprocket wheel 99 actuated in the manner which will be hereinafter described, and connected by a sprocket chain 9I to a sprocket wheel 92 fixedto the rearward end of an elongated shaft 93 which extends along under the tractor to the forward end thereof and which is provided beneath the shaft 18 (which is coincident with the axis of rotation of the turntable) with oppositely facing beveled gears 94 and 95. These gear wheels 94 and are loose on the shaft 93 and they both may be left loose thereon or may be selectively clutched thereto by means of a shiftable clutch member 95 splined on the shaft 93 and connectible with and disconnectible from cooperable clutch members (not shown) provided on the hubs of the gears 94 and 95. These gears 94 and 95 constantly mesh with a gear wheel 91 fixed to the lower end of the shaft I9. The gear I9 previously referred to is a double faced bevel gear and its upper teeth or gear member meshed with a corresponding beveled pinion 98 fixed to a short shaft 99 rotatably mounted in bearings I99 provided therefor in the frame IS. The shaft 99 has a sprocket I9l fixed thereto which acts through a sprocket chain I92 to drive a sprocket wheel I93 fixed to one end of the shaft I4 on which the driving roller I2 of the conveyor I9 is secured.

From the foregoing it will be understood that with the shaft 93 rotating the clutch 96 may be thrown in to cause the conveyor 19 to be driven.

The drive for the conveyor 55 and the digging wheel 6 is taken from the under gear teeth or under gear member of the double bevel gear 19, there being a pinion I95 meshing with this under gear member, which pinion is fixed to one end of a short shaft I96 journaled in spaced bearings I91 mounted on the turntable and having intermediate such bearings a sprocket wheel I98 fixed thereto. The sprocket wheel I98 drives a sprocket chain I99 which in turn drives a sprocket wheel II9 fixed on a short shaft IH journaled in bearings II2 provided on the turntable. A sprocket I I3 is fixed to the shaft III adjacent the sprocket I I9 and acts through a sprocket chain II4 to drive a sprocket wheel H5 fixed on the shaft 94 to which the driving roller 59 of the conveyor 55 is secured. On the other side of the roller 59 from that on which the sprocket wheel H5 is located a sprocket wheel H6 is fixed to the shaft 64 and acts through a sprocket chain II! to drive a sprocket wheel H8 fixed on the shaft GI (see also Figure 6). It will be understood from this description that a power drive is had for the conveyor 55 and is available whenever the clutch 95 is thrown in to drive the other conveyor 19. The drive for the digging wheel 6 is taken from the shaft 6|, a beveled pinion I29 fixed on one end of the shaft BI, meshing with a beveled gear wheel I2I fixed on this shaft 21 to drive the shaft and consequently its pinions I9 and 29.

It will be understood that by taking the drive for the conveyor I9 from the upper gear teeth of the beveled gear 19 and taking the drive for the conveyor 55 from the lower teeth of this gear ember that the range of swing or angular adjustment of the conveyor 19 is not limited by any interference between the pinions 98 and I95 through which the drives are taken.

It will be also noted that a shield 5 may be provided to insure the deposit of dirt discharged from the conveyor 55 onto the conveyor I9.

The mechanism for rotating the turntable 2 in either direction, which may be termed the swing gear, comprises a sprocket wheel I22 (see Figure 2) actuated in a novel manner, as will be hereinafter described, and connected by a sprocket chain I23 (see Figure 3a) with a sprocket wheel I 24 fixed to the rearward end of an elongated shaft I25, the forward end of which has oppositely disposed beveled pinions I26 loosely mounted thereon but selectively clutched thereto and constantly meshing with a beveled pinion I21 fixed to the lower end of a vertical shaft I28, the upper end of which has a pinion I29 fixed thereto, which pinion I29 meshes with an internal ring gear I39 securely fixed to the vertical flange-like portion 2 of the turntable 2.

With this construction, when the sprocket I22 is actuated the turntable may be swung in one direction or the other depending upon which of the beveled pinions I25 is clutched to the shaft I35. The action of an excavating machine of this sort and its ability to deal with the varying conditions met with in actual use is materially enhanced by the provision of a variable speed mechanism for controlling and effecting the swinging of the turntable in one direction or the other. The present invention proposes a novel and effective means for accomplishing this desirable result.

Referring now to Figure 9, there is illustrated a portion of the power plant P of the tractor. The numeral I 3i designates a shaft driven by the engine at engine speed. The shaft I3! is coupled to an alined shaft I3I which extends back into a gear box I32. Within the gear box or casing I32 a pinion I33 is fixed to the shaft I3! and meshes with gear wheel I34 fixed to a sleeve shaft I35 (see Figure 10) rotatably mounted on an inner solid shaft I36 (see Figure 11) the sleeve and solid shafts being appropriately supported for rotation in bearings provided therefor in the gear box. Integral with the body of the gear wheel I34 is an eccentric I31 with which an eccentric strap I38 is operatively fitted. The eccentric strap i38 has an integral arm I39 pivotally connected to a double crank arm I49 (see Figure 10) which may be formed integral with one end of a sleeve IAI mounted for rotation on a stud shaft I42 provided therefor within the gear box. The sleeve I4I also carries a rocker arm I43, the end of which is bifurcated and straddles a reciprocable rod I44. On the rod I44 is a fixed collar I45 engaging one side of the bifurcated end of the rocker arm. An adjustable collar I46 engages the other side of the bifurcated end of the rocker arm. The collar I49 is slidable along the rod I44 and its position is determined by adjusting a sleeve I41 which' is threaded to the rod, abuts the collar .lever controlled selective type. 'sion I drives a pinion I56 which meshes with I46. and is manipulated by a hand wheel I48. The inner end of the rod I44 is connected by a pin and slot connection I49 with the crank arm I56 of the driving member I5I of a one-way clutch I52. The driven member of this clutch I52 is fixed to the solid shaft I36.

With this construction and with the shaft I3I rotating .at a constant speed its pinion I33 and: consequently the gear wheel I34 and the -eccentric I31. turn at a constant rate.

The eccentric I 31 through its arm I39 rocks or oscillates the crank arm I40 together with its sleeve MI and the rocker arm I43. If the adjustable collar I46 is turned up to the position shown in Figure 12, the rocking or oscillation of the rocker arm I43 results in a corresponding reciprocation of the rod I44. As a result, on one stroke of the rod I44 the full motion of the rod is transmitted sequently free the collar I46 to an extent corresponding to that to which the sleeve is backed up, there will be lost motion between the rocker arm I43 and the rod I 44 .and a corresponding diminution in the amount of motion transmitted to the shaft I 36. Now then, as the sprocket wheel I22 is fixed on this shaft I36 it is apparent that a wide range of speeds may be transmitted to the swing gear. The swing gear may be caused to fairly creep or to move at .an approximately steady rate of speed. Moreover, a very large number of intermediate speed values are readily available by turning the hand wheel I48.

The traction drive is also taken from the shaft I3I through a transmission I55, shown diagrammatically in Figure 9, and preferably of the hand The transmisa gear wheel I51 whose shaft I58 is connected by means of gearing I 59 and I60 to the driving sprockets of the traction device.

Convenient reversal of the traction drive, in instances where low'feed traction (very slow speed traction) is desiredin which event the speed variation and reversal provided by the transmission I55 serving the range of high speed traction is not suitable-may be had by :incorporating 'a reversing gear mechanism in the gear box I32. In carrying out this purpose a drive pinion I6I is splined on the shaft I 36 and may be meshed with a driven pinion I62 fixed on one end of a shaft I63, the other end of which has a beveled pinion I64 fixed thereon and consequently meshing with the gear I51. The motion which the slidable pinion I 6I imparts to the driven pinion I62 whendirectly engaged therewith may be reversed by sliding, this pinion I6I back into engagement with a pinion I65 fixed on one end of a sleeve I66 supported for rotation within the gear box, said sleeve also having a second pinion I61 fixed thereon and constantly meshing with the driven pinion I62.

It will be understood that when the pinion I6I meshes with the pinion I62 and the transmission I55 is in neutral that the variable low speed transmission in the gear box I32 is interposed between the power plant and the self-laying tracks S, thereby providing for variable speed and power ratios in the low or feed traction.

The sliding 'gear I6I may be utilized to prevent retrograde motion of the shaft I36 by having coacting therewith an elongated pawl I68 pivotally mounted as at I69 within the gear box. The pawl is designed to idle over the teethof the pinion I6I when motion is imparted thereto and to its shaft I36 by the one-way clutch I52 on the rocking or active stroke of the rod I44 but holds the shaft I36 against movement on the return stroke of such rod.

In lieu of the pawl,a second one-way clutch may be associated with the shaft I36 and arranged to operate oppositely with respect to the one-way clutch I52. The outer member of this clutch I'III is braked by means of a brake band III. With this construction, when the one-way clutch I52 .actuates the shaft I36 the second oneway clutch I'Ill idles but on the return or inactive stroke of the rod I44, during which the oneway clutch I52 idles, the second one-way clutch I10 holds the shaft I36 against retrograde movement.

With a machine constructed in this manner the tractor or other power plant employed rotates the digging wheel 6 which, under the control of its hoisting mechanism, is positioned in effective digging relation to the material to be excavated. As the digging wheel rotates the turntable is swung at the desired speed and with adequate power, the values of which may be selected by the operator. As the digging wheel is positively constrained to follow the turntable in its swinging movement, the digging Wheel is thrust with requisite power against the material to be excavated or handled. As the material is excavated by the action of the cutting blades 24, their teeth 25 and the teeth I4 of the buckets I I, it is gathered up by the digging buckets I I and carried up along the shield 56 to the trough 51 through which it slides onto the conveyor 55. The conveyor 55 carries the material up onto the conveyor 10 which is positioned to transfer the excavated material to the selected point of deposit. The machine may be advanced an appropriate increment between swings or cuts or may be slowly advanced as the cutting progresses during each swing.

A self-contained mobile unit of light weight but of unusual digging capacity is provided. Moreover, the provision made for raising and lowering the digging wheel increases the range of its action.

As hereinabove described and as shown in the drawings, the excavating means proper is preferably in the form of a digging wheel. Obviously, however, many of the advantages of the present invention may be had with a different or equivalent type of excavating means.

While I have shown and described one type of machine in which the invention may be embodied, it is to be understood that the machine shown has been selected merely for the sake of illustration and that various changes in the size, shape and arrangement of the parts and in the selection of the auxiliary accessories and instrumentalities may be resorted to without departing from the spirit of the invention and the scope of the subjoined claims. a

The invention claimed is:

1. An excavating machine comprising a tractor having traction devices, a power plant and controllable gearing between the power plant and the traction devices affording high and low traction speeds for the tractor, a digging wheel disposed forwardly of the tractor with its wheel plane substantially vertical and transverse to the line of feed of the tractor, means supporting said wheel from said tractor for rotation, for transverse bodily swinging movement and for raising and lowering movement relative thereto, said means constraining said wheel to partake of the feeding movement of the tractor, means for raising and lowering said wheel, means for rotating said wheel and m ans operable from said gearing for swinging said wheel at variable speed and power ratios.

2. An excavating machine comprising a mobile frame, traction devices therefor, a power plant thereon, controllable mechanism actuated from said power plant and connectible with said traction devices to provide variable rates of high and low traction speeds for the frame, a digging wheel having its wheel plane transverse to the line of feed of the frame, means supporting the wheel from the frame for rotation, transverse bodily swinging and raising and lowering movement relative thereto, said means constraining said wheel to partake of the feeding movement of the frame, means for raising and lowering said wheel, means for rotating said wheel, means operable from said mechanism for swinging said wheel at variable speed and power ratios, and conveying means movable with the frame for conveying the excavated material from the digging wheel to a point of deposit.

3. An excavator comprising a mobile frame, traction devices therefor, a power plant thereon, a driving connection between said power plant and said traction devices whereby to provide for a traction feed of said frame, a digging wheel having its wheel plane disposed transversely to the line of feed of said frame, means supporting said wheel from said frame for rotation about its own axis, for bodily swinging movement transversely to the frame and for raising and lowering movement, means operable to rotate said wheel, means operable to raise and lower the same, a variable speed gear set actuated from said power plant and connectible to said Wheel for bodily swinging the same, and conveying means movable with the frame, for receiving the excavated material from the wheel and carrying the same to a point of deposit.

4. An excavator comprising a mobile frame, traction devices therefor, a power plant thereon, a driving connection between said power plant and said traction devices whereby toprovide for a traction feed of said frame, a digging wheel having its wheel plane disposed transversely to the line of feed of said frame, means supporting said wheel from said frame for rotation about its own axis, for bodily swinging movement transversely to the frame and for raising and lowering movement, means operable to rotate said wheel, means operable to raise and lower the same, a variable speed gear set actuated from said power plant and connectible from said wheel for bodily swinging the same and comprising a constant speed driving member actuated by said power plant, a driven member connectible with said digging wheel for bodily swinging the same and a lost motion connection of variable amplitude between said driving and driven members.

5. An excavator comprising a mobile frame, traction devices therefor, a power plant thereon, a driving connection between said power plant and said traction devices whereby to provide for a traction feed of said frame, a digging wheel having its wheel plane disposed transversely to the line of feed of said frame, means supporting said wheel from said frame for rotation about its own axis, for bodily swinging movement transversely to the frame and for raising and lowering movement, means operable to rotate said wheel, means operable to raise and lower the same, a variable speed gear set actuated from said power plant and connectible with said wheel for bodily swinging the same and comprising a driving gear wheel rotated at a constant rate of speed from said power plant, a rocker arm oscillated from said gear wheel, a one-way clutch connectible with said digging wheel for bodily swinging the same, actuating arm. for said clutch and a variable I npiitude lost motion connecting means between sa d rocker arm and said actuating arm.

6. An excavator comprising a mobile frame, traction devices therefor, a power plant thereon, a driving connection between said power plant and said traction devices whereby the latter may be utilized to provide a traction feed for said frame, a turntable supported on the forward end of said frame, a digging wheel disposed forwardly of said frame with its wheel plane transverse to the line of feed thereof, means interconnecting the digging wheel with the turntable to constrain the wheel to partake of the feed of the frame and of the swing of the turntable while leaving the wheel free for rotation about its own axis and for raising and lowering movement, means operable to raise and lower the wheel, means operable to rotate the wheel, a variable speed gear set actuated from said power plant and connectible with the turntable to swing the same at variable speed and power ratios, and conveying means movable with the frame for conveying material from the diggging wheel to a point of deposit.

'7. An excavator comprising a mobile frame, traction devices therefor, a power plant thereon, a driving connection between said power plant and said traction devices whereby the latter may be utilized to provide a traction feed for said frame, a turntable supported on the forward end of said frame, a digging wheel disposed forwardly of said frame with its wheel plane transverse to the line of feed thereof, means interconnecting the digging wheel with the turntable to constrain the wheel to partake of the feed of the frame and of the swing of the turntable while leaving the wheel free for rotation about its own axis and for raising and lowering movement, means operable to raise and lower the wheel, means operable to rotate the wheel, a variable speed gear set actuated from said power plant and connectible with the turntable to swing the same at variable speed and power ratios, and conveying means movable with the frame for conveying material from the digging wheel to a point of deposit, in combination with a reversing gear set interconnectible with the variable speed gear set and the driving connection to modify the action of the latter so as to provide for reversal of the action of the traction devices in a low speed range.

8. In combination with a tractor having a frame, a power plant, supported on said frame, said frame projecting forwardly of said power plant and self-laying tracks supporting said frame, a turntable supported on the forward end of said frame, a digging wheel disposed with its wheel plane transversely of the tractor, means connecting said wheel to said turntable to constrain the wheel to turn therewith, means actuated from the power plant to rotate said wheel and to swing said turntable, and means for carrying off the material excavated by said wheel.

9. An excavator comprising a tractor having a frame, self-laying tracks supporting said frame, a power plant on said tractor and a power drive between said power plant and said tracks, a turntable mounted on said frame, a digging wheel supportedby said turntable and constrained to move therewith,- a variable slow speed gear set actuated from said power plant, means actuated by said gear set for swinging said turntable, means 10 traction devices therefor, a power plant on said operable from said gear set for imparting low feed traction to said tracks, and means operable to rotate said digging wheel.

10. An excavator comprising a mobile frame,

frame, a driving connection between said power plant and said traction devices whereby the latter may be utilized to provide a traction feed for said frame, a turntable supported on the forward end of said frame, a digging wheel disposed forwardly of said frame and interconnected with said turntable to be constrained to swing there-' with while free to raise and lower relative thereto, hoisting'means for raising and lowering said digging wheel, and a conveyor mounted on said turntable for receiving excavated material from said digging wheel and conveying the same to a point of deposit.

11. Anexcavator comprising a mobile frame,

traction devices therefor, a powerplant on said frame, a driving connection between said power plant and said traction devices whereby the latter may be utilized to provide a traction feed for said frame, a turntable supported on the forward end of said frame, a digging wheel disposed forwardly of said frame and interconnected with said turntable to be constrained to swing therematerial from said first-named conveyor' and having its other end extending rearwardly therefrom, and means for controlling the position of said second-named conveyor.

12. An excavator comprising a mobile frame, a turntable supported for rotation thereon, a digging wheel, a supporting member on which said digging wheel is rotatably mounted with its Wheel plane transverse to the line of feed of said frame, said turntable having upright frame members, links pivotally and positively connecting said frame members and said supporting member,

' means constraining said links to vertical movement,hoisting mechanism for controlling the elevation for said supporting member and its wheel, means operable to rotate-said wheel, means operable to swing said turntable, means for carrying off material from said wheel to a point of deposit. 13. An excavator comprising a mobile frame, traction devices therefor; a power plant thereon, a driving connection between the power plant and the traction devices to provide for a traction feed of said frame, a turntable'supported for rotation on said frame, a digging wheel, a supporting member on which said digging wheel is mounted for rotation with its wheel plane transverse to the line of feed of the frame, links positively and pivotally connecting said turntable and said supporting member and constraining the supporting member and wheel to partake of the feed of the frame and of the swinging movement of the turntable while leaving the member and wheel free for raising and lowering movement and the wheel free to rotate, hoisting mechanism for controlling the raising and lowering of its supporting member and its wheel, means for rotating said wheel, and a variable speed driving connection between the power plant and the tumtable for swinging the turntable at variable speed and power ratios.

14. An excavator comprising a mobile frame, a turntable supported for rotation thereon, a digging Wheel, a supporting member on which said wheel is mounted for rotation, said turntable having upright frame members, links positively and pivotally connecting said frame members and said supporting members, hoisting mechanism for controlling the elevation of said supporting member and its wheel, means for rotating said wheel,

means for rotating said turntable, a conveyor ging wheel, a supporting member on which said 5 digging wheel is rotatably mounted with its wheel plane transverse to the line of feed of said frame, means interconnecting said supporting member with said turntable to constrain the same to swing therewith and to impart the feeding movement of the frame thereto, means controlling the vertical position of the supporting member, means for swinging said turntable, a plurality of cutting blades disposed forwardly of and extending transversely of said wheel and connected thereto adjacent their outer ends, and means between the inner end portions of the blades and the supporting member for taking up the thrust exerted during the excavating operation of said blades.

16. Mechanism of the class described comprising a turntable, a digging Wheel carried by said turntable, an endless belt conveyor mounted on said turntable and positioned to receive material fromsaid digging wheel and a spoils conveyor having one end positioned to receive material from said first mentioned conveyor in all positions thereof, said spoils conveyor itself being shiftable to deliver material to selected points of deposit.

17. The invention set forth in claim 16 and further characterized by a common drive for said digging wheel, said first mentioned conveyor and said spoils conveyor.

ROBERT L. BROWN. 

